A white solid compound (UF6) of → uranium and
→ fluorine obtained by chemical treatment
of → yellowcake, forming a vapor at temperatures
above 56 °C. It contains both of the naturally occurring
→ isotopes of uranium U-235 and U-238.
The isotopes are separated on the basis of differences in their diffusion
properties. UF6 is the process medium for all separation
processes for → uranium enrichment.
It is essential that fluoride be a
pure element and therefore solely the mass differences of U-235 and
U-238 determine the separation process.